Question

Lavandula Grosso   QUESTION: Hello Leroy,
I have grown lots of lavenders, in different gardens, under different conditions, all in Santa Cruz county, near the ocean in central California.  I can't help but notice how much of a failure rate there is.  I am talking about mainly english lavender cultivars, such as provence, grosso and munstead.  I am including a picture of Grosso lavender growing in very good, silty, well drained soil. The others around it are doing well.  My question is: what do lavenders really need to thrive in my area?

ANSWER: Lesley:
I have grown Grosso & Provence. I found that they do well with lime added to soil and worked in once a year. Spread within the diameter of the plant. Prune them every 3 weeks during the summer & early fall. They will give new growth when pruned on schedule.

Leroy

www.ask the herbman.com

---------- FOLLOW-UP ----------

QUESTION: Thank you!  I have not heard of lime and I will try that.  My follow up questions are: how much lime do I add?  Should I let a pH tester decide that, or is there a cup amount for each plant?  The other question I have is, what if the plant is blooming when pruning time comes?  Here in Santa Cruz, lavenders bloom starting around late June and keep going until August, at least.  I thought Grosso only bloomed once a year.  Do you think it would rebloom if I pruned it back?  And are you recommending that I prune by thinning, or by shearing?
Thank you for your time,
Lesley

Answer
Lesley:
If your plants are a few years old, I would use 1 cup per plant. I am not sure about the re-blooming, but thinning them will make them more healthy and vigorous. Use 1 or 2 plants as a test for this year for testing. I have only used the powdered lime. The granules should be ok too!

Leroy